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©FluentInc.2020/6/[e-mail]©FluentInc.2020/6/132FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterOverviewofMoving/DeformingMesh(MDM)capabilitiesZonalMotionSpecificationInDepthLookUDFwritingforMDMExamplesConcludingRemarksQ&A©FluentInc.2020/6/133FLUENTSoftwareTrainingUGM2002FluentUserServicesCenter©FluentInc.2020/6/134FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterFluent6.0offersthreemodesofmeshdeformationSpringanalogyLocalremeshingDynamiclayeringMDMproblemsgenerallycomplex;multiplestrategiesmaybenecessary.©FluentInc.2020/6/135FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterUsercanlocalizemeshmotionbyspecifyingthezonesforwhichhe/shewantstousedynamicgrid.MeshmotioninvariouszonesmayusedifferentstrategiesConnectivitybetweenadjacentdeformingzonesmaybenon-conformalinterfacemaydeform©FluentInc.2020/6/136FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterPrescribedboundarymotionInteriornodesbehavelikeaspringor‘sponge’nodesmoothing:nodepositiondependsonneighboringnodes(iterativeprocess)ConnectivityinformationremainsunchangedLimitedtorelativelysmalldeformationwhenusedasastand-aloneschemeApplicabletoboundaryandvolumemeshes.Currentlyimplementedfortri/tetmeshesonly©FluentInc.2020/6/137FLUENTSoftwareTrainingUGM2002FluentUserServicesCenter©FluentInc.2020/6/138FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterDescriptionUsefulforlinearmotionextrusionapproach(rectilinear)cellsareadded/deletedasregiongrows/shrinksaslayersareadded/deleted,connectivitychangesApplications:pistons,valvesApplicabletovolumeandboundarymeshAvailableforquad,hexandprismelements©FluentInc.2020/6/139FLUENTSoftwareTrainingUGM2002FluentUserServicesCenter©FluentInc.2020/6/1310FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterPurerectilinearextrusionWillgenerateskewedcellsiffacenormalnotalignedwithextrusiondirectioninapplicableforexcessivecurvatureCurrentlynoprojectionoflayersideontogeometrylayersidemustbecylindrical(linearfor2D)©FluentInc.2020/6/1311FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterLayeringinoneregionSpringanalogyandremeshing.Deformingboundaryzonesnon-conformalinterfacewall©FluentInc.2020/6/1312FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterDefineDynamicMeshParametersMethodstogglespring,layering,remeshingapproachesguidynamicallychangestoreflectselectedmethodsDynamicMeshModelenablesgenericfunctionalityIn-CylinderoptionaddsspecificfunctionalitydefinitionofRPM,startingcrankangle,crankperiod,etc...optionenablesICspecificprofileformatforvalvemotion©FluentInc.2020/6/1313FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterSmoothing(spring)parameters‘stiffness’boundarynoderelaxationconvergencetolerance(max)numberofiterationsLayeringparameterssplit/collapsefactorRemeshingparametersmin/maxvolumemaxskewness©FluentInc.2020/6/1314FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterFluenthandlesvolumedeformationautomaticallybasedonthemotionoftheboundingsurfaces.Avolumewilldeformonlyifthereisrelativemotionbetweenitsboundingsurfaces.UserdoesnotexplicitlyneedtodefinemotioninsidethedeformingvolumeTrueforsmoothing,remeshingandlayering.©FluentInc.2020/6/1315FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterSpring/remeshingexample:BottomwallSpecifiedrigidbodymotionAlsospecifyremeshingcellheightforadjacentdeformingfluidzoneFluidZoneFluentautomaticallyhandlesremeshingNozonespecificinputsSidewallsDeformationduetomotionofadjacentrigidbodymotionMustberemeshedRequiresremeshinginputscylindricalaxis,radiuscellheightTopwallStationary,norequiredinputs©FluentInc.2020/6/1316FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterLayeringexample:BottomwallSpecifiedrigidbodymotionAlsospecifylayeringheightandheightfactorofadjacentcellzoneFluidZoneFluentautomaticallyhandleslayeringNozonespecificinputsSidewallsDeformationduetomovingbottomwall,but…DefinedbyextrudedcelllayersideNorequiredinputsTopwallStationary,norequiredinputs©FluentInc.2020/6/1317FLUENTSoftwareTrainingUGM2002FluentUserServicesCenterCombinationofapproachesLayeredFluidZoneLayeringonlyoccurswhenthereisrelativemotionbetweenthebottomwallandlayeredcellsRemeshedFluidZoneSmoothing/Remeshingonlyoccurswhentheinteriorzoneseparatingthe